Robotic interventional systems and devices are well suited for performing minimally invasive medical procedures as opposed to conventional techniques wherein the patient's body cavity is open to permit the surgeon's hands access to internal organs. Advances in technology have led to significant changes in the field of medical surgery such that less invasive surgical procedures, in particular, minimally invasive surgery (MIS), are increasingly popular.
A MIS is generally defined as a procedure that is performed by entering the body through the skin, a body cavity, or an anatomical opening utilizing small incisions rather than large, open incisions in the body. With MIS, it is possible to achieve less operative trauma for the patient, reduced hospitalization time, less pain and scarring, reduced incidence of complications related to surgical trauma, lower costs, and a speedier recovery.
MIS apparatus and techniques have advanced to the point where an elongated catheter instrument is controllable by selectively operating tensioning control elements within the catheter instrument. In one example, four opposing directional control elements wind their way to the distal end of the catheter which, when selectively placed in and out of tension, cause the distal end to steerably maneuver within the patient. Control motors are coupled to each of the directional control elements so that they may be individually controlled and the steering effectuated via the operation of the motors in unison.
However, in some clinical situations, it is not possible to use an elongate instrument with multi directional control elements. For instance, in some MIS procedures a microcatheter is used that does not have any steering element. Elongate instruments having multiple driving elements are typically larger in diameter and sometimes cannot pass through the naturally occurring lumens within the body (e.g., veins or arteries). In these MIS procedures, navigation can be performed with a much simpler non-steerable pre-curved catheter. These catheters can be navigated by simply rotating the pre-curved tip, while feeding the catheter into the lumen.
Robotic systems that are designed with directional control often have limited capability to rotate the entire elongate instrument. It is not necessary to rotate the entire instrument because there is complete direction control at the tip by selectively placing the directional control elements in and out of tension. However, if non deflectable instruments are attached to these robotic systems, greater rotational capability of the entire device is needed. If multiple control motors are present in a robot system that is typically used for steering a steerable catheter, it can be inconvenient or not possible to switch out the multiple motor control system, and enable it to use the simpler non-steerable device to provide catheter rotation capability.
As such, there is a need for a robotic system that can activate the directional control elements when steerable devices are attached to it and can also be used to rotate the entire device when non steerable devices are attached to it.